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#include <stdio.h>
#define MAXALLOCS 1000
#define SIZE 50
extern char *sbrk();
extern char *malloc();
main()
{
char *ptr[MAXALLOCS];
char *obrk, *nbrk;
int i;
obrk = sbrk(0);
printf("break is initially 0x%x\n", obrk);
for(i = 0; i < MAXALLOCS; i++) {
ptr[i] = malloc(SIZE);
}
nbrk = sbrk(0);
printf("break is 0x%x (%d bytes sbrked) after %d allocations of %d\n",
nbrk, nbrk - obrk, MAXALLOCS, SIZE);
for(i = 0; i < MAXALLOCS; i++) {
free(ptr[i]);
}
nbrk = sbrk(0);
printf("break is 0x%x (%d bytes sbrked) after freeing all allocations\n",
nbrk, nbrk - obrk);
fflush(stdout);
/* Should be enough memory for this without needing to sbrk */
(void) malloc(SIZE * (MAXALLOCS / 2));
nbrk = sbrk(0);
printf("break is 0x%x (%d bytes sbrked) after allocating %d\n",
nbrk, nbrk - obrk, SIZE * (MAXALLOCS/2));
exit(0);
}
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